According to the Department of Veterans Affairs, hearing problems—such as hearing loss and tinnitus, a ringing or buzzing in the ears—are the leading conditions for service-connected disability compensation. This is because hazardous noise exposure from military activities can cause hearing damage, known as auditory injury.

Why is Noise a Common Military Hazard?

Military personnel can be repeatedly exposed to excessive noise over years of service, but even a single, unprotected exposure to an extremely loud noise, such as from a firearm or other weapon system, can cause auditory injury. However, weapons account for only a portion of military activity noise exposure.

“Some of the loudest environments in the military are aircraft carriers, flight lines, helicopters, and naval ship engine rooms,” said U.S. Army Lt. Col. Kerri Klingseis, audiologist and chief of the hearing conservation and readiness branch, or HCRB, at Defense Health Agency Public Health.

Klingseis said the three feet rule is a good general rule for noise exposure.

“Any activity, even riding in a Humvee, can expose a rider to hazardous noise levels,” said Klingseis. “A general rule is the three feet rule: If you can’t hear someone speaking at arm’s length, the noise is too loud and can cause temporary hearing loss. Over time, repeated noise exposure without hearing protection can cause permanent hearing loss or tinnitus.”

Chronic noise-induced hearing loss can negatively affect the lives of veterans and active duty service members. In military settings, even slight deterioration of hearing can impact a service member’s ability to differentiate between friendly or enemy sounds and to hear radio communications accurately. Hearing readiness is critical for reducing risk to a service member’s life, or that of their unit.

How Does the Military Monitor Hearing?

To identify personnel who may have early signs of noise-induced-hearing loss the Department of Defense requires annual hearing tests, recorded on audiograms.

“Audiograms chart the volume at which a person hears different pitches,” said Klingseis. “Annual testing ensures service members maintain the hearing capabilities required to deploy, perform assigned duties, and comply with the medical retention standards required for their positions. The requirements ensure personnel are ‘hearing ready’ to safely conduct combat operations.”

DOD’s hearing test results are captured in the electronic Defense Occupational and Environmental Health Readiness System-Hearing Conservation, known as DOERHS-HC, so they can be compared to previous test results to determine if hearing might be deteriorating, said Deborah Lake, a senior audiologist in the HCRB.

“Personnel who require additional testing are flagged for medical evaluation by an audiologist,” said Lake. “DOEHRS-HC also helps DOD public health experts identify high-risk activities or locations where hearing protection procedures may need to be evaluated.”

Why Did the Military’s Hearing Testing Program Need Improving?

DOD hearing testing has traditionally been conducted in multi-person, sound-treated booths, said Benjamin Sheffield, a hearing investigator supporting DHA-PH. “One million service members are enrolled in the program, so to meet deployment readiness demands, the booths are typically set up to test eight people simultaneously.”

Sheffield explains that COVID-19 social distancing requirements caused a major obstacle. The backlog of service members not tested meant a drastic reduction in the numbers of personnel ready to deploy.

To help increase hearing readiness testing, Sheffield and other military audiology experts supported a DHA-PH pilot program to use boothless audiometers, and they documented the findings in a November 2023 study published in Military Medicine.

How do Boothless Audiograms Help the Military?

“Boothless audiometers were proposed as a solution to allow for increased throughput of hearing exams in the context of a pandemic,” said Devon Kulinski, audiologist from the Walter Reed National Military Medical Center and study co-author.

“As the name implies, boothless audiometers enable valid hearing testing outside of the typical fixed-sound isolated booth through the use of specifically designed headphones and software,” said Kulinski. “In addition to increased efficiency and cost and space savings, boothless testing provides a more comfortable testing environment for patients.”

Because the sound booth method is designed to eliminate all background noise and distractions to ensure accurate results, the biggest concern during the pilot program was the accuracy of the boothless system.

“The effectiveness of the technology was our question,” said Kulinski. “Our study showed that results obtained from boothless audiometers were comparable to results obtained from the standard sound isolated booth.”

Has the Boothless Audiology Been Accepted by the Military?

Lake explains that over 17,000 boothless audiology exams have been conducted around the world since 2021. Clinician and patient feedback have been positive.

Vikki Bugtong, senior program manager at the DOD’s Hearing Center of Excellence, described enthusiastic comments she heard from various military audiologists about the new technology.

“A fully contained and transportable hearing test system inspired them to think about all the uses for this product,” said Bugtong. “For military installations that may not have sound booths, boothless audiometry provides an opportunity to meet annual testing requirements locally so service members don’t have to travel long distances.”

Bugtong said service members themselves are excited to be using this new technology.

“One U.S. Army installation had started using the boothless testing in April 2021,” said Bugtong. “We were returning to work from COVID-19 and were social distancing and wearing masks indoors. From the start, every patient tested liked it better than testing in the booth because they were not confined to a small claustrophobic space for the test.”

Bugtong shared patients’ feedback on boothless audiology.

“Some patients said that it was ‘cool’ or exciting; others were glad to avoid the claustrophobic box,” said Bugtong. “Several said that the headphones were more comfortable than the headphones in the booth, and one said that he did not hear his heartbeat like he did with traditional headphones. Another said that he liked that there were no wires.”

Audiologists are also hearing about this new hearing test system from their command, said Bugtong.

“Military leaders were learning about the U.S. Army’s successes using the boothless audiometry and wanted to bring the technology to their installations,” said Bugtong. “Some clinics have reached out to learn how they could purchase the products.”

Both Bugtong and Sheffield also noted the boothless technology will allow military audiologists to monitor service members’ hearing in austere environments like deployment locations and garrison weapons firing ranges. This means audiologists can immediately determine if the weapon noise results in a temporary noise-induced hearing loss.

How Else Can Boothless Technology Help the Military?

“While the initial motivation to use boothless audiometry was to increase hearing testing capacity to maintain a medically ready force, we have found other benefits from the technology,” said Sheffield. “For example, we have used the new system to reduce masking and tinnitus referrals and have been able to provide more individualized hearing health education and training.”

Sheffield noted that the boothless technology will now also be critical to meet the requirements of the DOD policy updated in December 2023. This policy requires fit testing to verify service members achieve proper fit of their hearing protection.

“Now we are working to incorporate the capability to test the fit and effectiveness of a service member’s hearing protection, such as earplugs or earpro,” said Nancy Vause, a senior HCRB hearing conservation consultant with DHA-PH, who has fit-tested service members’ hearing protection for weapons systems for several years.

“Real-time testing will improve how we train service members to wear their hearing protection, so they know ‘what right feels like,’ said Vause. “Just like any warrior tasks—even though they learn correctly once, they must practice correctly fitting and wearing their ‘earpro’ regularly.”

Are Boothless Audiograms Available to all Service Members?

“Boothless audiometry is an innovative technology that will help to modernize hearing conservation across the services,” said Klingseis. “First deployed by the U.S. Army, there have been many obstacles in getting these devices to be more widely accepted across all the DOD services. But boothless tests are now being used in some capacity by the U.S. Air Force and the U.S. Navy.

Boothless testing won’t replace existing equipment but will soon be a standard component augmenting all military hearing programs—to ensure a ready force and improve military efforts to conserve the hearing of active duty personnel and veterans.